A baseline prostate-specific antigen (PSA) level among men at midlife appears to be highly correlated with the risk of developing lethal prostate cancer within their lifetimes. These results were recently published in the Journal of Clinical Oncology.
Prostate cancer is the second leading cause of cancer-related deaths among men in the United States. Recently, screening procedures for prostate cancer have come into question in terms of their effectiveness of improving overall survival when weighed against unnecessary treatment and associated side effects for men with the disease.
Some prostate cancers can grow very slowly, while other prostate cancers are more aggressive in nature. Among men with slow-growing prostate cancer, a viable option for them is to monitor the cancer, and initiate treatment once the cancer becomes threatening. Among men with faster-growing prostate cancers, treatment tends to be initiated upon diagnosis.
An important issue with screening for prostate cancer is determining who will benefit most from the screening procedures, so that over-treatment for the disease is reduced, and improvements in survival are achieved.
A PSA is one screening method that tests for levels of the PSA protein in a patient’s blood. The PSA protein is normally secreted by the prostate into the blood. However, the existence of prostate cancer tends to produce higher than normal concentrations of PSA in circulating blood. Conditions of the prostate that are not cancerous can also result in higher PSA blood levels. This means that additional testing is required among men with higher than normal PSA levels to truly determine whether prostate cancer is present.
Researchers involved in the Physicians’ Health Study, a trial that included 22,071 male physicians initiated in 1982 to explore potential effects of aspirin and beta-carotene consumption, recently evaluated data from the trial that included PSA levels in midlife among participants. Follow-up of this trial is 30 years.
- Men whose baseline midlife PSA level was within the highest 10% in their age group had a significantly higher rate of developing lethal prostate cancer within their lifetime compared to men whose baseline midlife PSA level was in the median range or lower.
- Specifically, men aged 40-49 years with PSA levels in the highest 10% of their age group had an 8.7-times increased rate of developing lethal prostate cancer; men aged 50-54 had a 12.6-times increased rate of developing lethal prostate cancer; and men aged 55-59 years had a 6.9-times increased rate of developing lethal prostate cancer than their counterparts whose baseline midlife PSA level was at median range or less.
The researchers suggested that according to results from this study, “Risk-stratified screening on the basis of midlife PSA should be considered in men age 45 to 59 years.” Men aged 45 years and older should speak with their physician regarding PSA testing and prostate screening schedules.
Reference: Preston M, Batista J, Wilson K, et al. Baseline prostate-specific antigen levels in midlife predict lethal prostate cancer. Journal of Clinical Oncology. 2016; 34 (23): 2705-2711.